We did a short tip to Croatia a while ago, we took the bus to go from Dubrovnik to Split and it was honestly the most beautiful bus ride in my whole life. We rode along the Adriatic coast, clean bus, good driver, pleasant fellow passengers.
- The ride was only 4.5hrs
- When we were passing through Bosnia, the border officer came up to do passport check. No fuss - Expect longer border hours in rush season in July and August
- I checked a ticket would cost 125 HRK (about 17euro, 20usd) - mind they don't use euro in Croatia
- You can book the tickets ahead of time online, back then we just went to the bus terminal in Dubrovnik and got the tickets there. There are many buses each day, I would assume it's advisable to book if you are going during peak season though